Regulatory Permitting Assistance, including NPDES and WDR
City of Atwater, California

West Yost was first retained by the City of Atwater (City) to assist with the development of a formal comment submittal to the Regional Water Quality Control Board in response to the Tentative Waste Discharge Requirements (WDRs) for the City’s 6.0 mgd Wastewater Treatment Plant (WWTP). West Yost raised several technical issues identified in the Tentative WDRs, many of which were resolved through discussions with Regional Board staff. The permitting team’s remaining concerns caused the Regional Board to withdraw the Tentative Permit from consideration to give the City and the Regional Board an opportunity to further evaluate some of the outstanding technical issues.

A second Tentative Permit was issued. Again, West Yost raised several technical issues that were addressed through the permit negotiation process. However, the Regional Board indicated that a single fixed ammonia limit based on assumed worst-case conditions would be applied. The fixed limit presented the City with a major risk of discharge violations.

At a subsequent Regional Board hearing, West Yost (on behalf of the City) contested the application of the ammonia limitation in the permit. As a result of the compelling evidence presented, the Regional Board remanded the permit for re-consideration of the ammonia limitation. West Yost worked in cooperation with Regional Board staff to develop an appropriate approach for applying effluent ammonia limitations that is in accordance with EPA guidance documents but not unreasonably over-protective. A final permit, with the revised ammonia limitations, was adopted in June 2007 and the approach developed is the current standard used by the Regional Board in all permits.

West Yost also performed several studies required under the new permit, including a Temperature Study; a Hardness Study to define the appropriate hardness value for deriving metals criteria; a collection system sampling study to evaluate potential sources of dioxin discharges to the WWTP; and a Pollution Prevention Plan.

Ongoing regulatory program management services have included the development of an overall compliance strategic plan that involves the construction of a new WWTP. In addition, West Yost has provided services as the City’s WWTP facilities design team for this facility, which will be online by the end of 2011.

In support of the new WWTP, West Yost developed a Report of Waste Discharge, processed and obtained approval from State Board for a Petition to Change the Point of Discharge, and provided support in the completion of CEQA efforts. To help facilitate the adoption of the permit by October 2011, West Yost developed (at the request of Regional Board staff) the initial draft of the new permit, including all the necessary data analysis.